ABSTRACT
Two antimicrobial peptides namely bovine tracheal antimicrobial peptide [TAP] and bovine neutrophil beta-defensin 4 [BNBD4] were investigated in crossbred Frisian and Egyptian native cattle. TAP and BNBD4 were tested for reaction with cDNA of various cattle tissues such as liver, lung, trachea, intestine, mammary gland, colon and blood using PCR. TAP and BNBD4 were positive in all tissues of the native cattle whereas in crossbred Frisian only the trachea PCR- product sequence was positive with both. NCBI-Blast analysis of TAP and BNBD4 sequences showed 89% and 92% alignment between crossbred Frisian and native cattle, respectively. Blast analysis of TAP PCR-product sequences of both native and crossbred Frisian cattle with GenBank published sequences revealed sequence homology between both native and crossbred Frisian cattle and Bos taunts TAP mRNA. Analysis also revealed homology [90%] between crossbred Frisian TAP and Bos taunts lingual antimicrobial peptide [LAP], whereas native cattle TAP was homologous [86%] to Bubalus bubalis LAP. Blast analysis of BNBD4 PCR-products sequence revealed sequence homology between both native and crossbred Frisian cattle and Bos taurus BNBD4 mRNA. Analysis also revealed homology with Bubalus bubalis enteric beta-defensin preproprotein mRNA, however the native cattle showed higher homology [128 nucleotide shared] than the crossbred Frisian where only 62 nitcleotides were shared. The presence of TAP and BNBD4 in all tested tissues of native cattle may reflect a higher tendency towards disease resistance in native cattle compared to the crossbred Frisian ones. Further studies on the expression of these genes in different organs of the native cattle will shed more light on their disease resistance